import re
s = '''
<div class="news">
    <div class="content">
      <h3>This is a header</h3>
    </div>
     <div class="content">
      <h3>This is a heade2r</h3>
    </div>
</div>
'''
result = re.findall(r' <div class="content">([\s\S]*?)</div>', s)
# result = re.findall(r'<h3>([\s\S]*?)</h3>', s)
print(result)